Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   502 EFI problems again (https://www.offshoreonly.com/forums/general-q/354614-502-efi-problems-again.html)

deboatmon 06-13-2018 09:36 AM

502 EFI problems again
 
Started motors first time this year and starboard motor won't idle in gear. Sputters and gags. Motor runs but drops out for an instant here and there while underway. Tach bottoms out when engine cuts out. Any way tach causes this ? Gaffrig tach 10 years old. I remove batteries every winter and it seems logical I maybe missed a ground wire or similar.

Motors ran fine when I pulled batteries out last October.

Any ideas at all ? Help !

Pismo10 06-13-2018 09:43 AM

Spray Gumout on the flame arrestor while it is dying. If it catches, you immediately know it is a fuel problem. If it does not, then it is a spark problem. Instatly identify the difference this way. Very helpful.

deboatmon 06-13-2018 02:38 PM

Unfortunately I can't spray anything in the flame arrestor while underway. It doesn't sputter and quit, it's like the ignition is turned off for a millisecond.

Griff 06-14-2018 12:49 AM

I highly doubt its the tach. My guess is VST system is partially clogged.

Tractionless 06-16-2018 05:57 PM

Plugs, wires, cap, rotor, fuel filters all recently done? Timing checked? Last IAC motor replacement? Fuel pickup in tank clear? Any ball valves or 90's in the fuel lines clear? Coolant temp. sensor checked? Swap coils then ignition module then map side to side to see if the problem switches sides. If all this checks out see VST per Griff. Can you tell I've been chasing an idle issue as well?


All times are GMT -5. The time now is 10:06 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.